1. Field of the Invention
The present invention relates to an apparatus having a carriage scanning mechanism for reciprocally scanning a carriage, and a recording apparatus, an information recording/reproducing apparatus, an information recording apparatus, an information reproduction apparatus, an information reading apparatus and an information erasing apparatus, provided with the apparatus including the carriage scanning mechanism.
2. Related Background Art
For most of the conventional apparatuses that perform recording/reproducing/reading using a head mounted on a carriage, in synchronization with the reciprocal displacement of the carriage in the main body of the apparatus, a motor fixed to the main body of the apparatus exerts a driving force that is transmitted to the carriage by a timing belt and that reciprocally moves the carriage.
FIG. 19 is a diagram illustrating the arrangement of a conventional serial recording apparatus.
In FIG. 19, rotatably mounted in an apparatus main body 100 is a paper feed roller 111, which is rotated by a paper feed motor 112, that is employed to feed a recording sheet 113. In order for the recording sheet 113 to be conveyed, follow-up rollers 114 press it against the paper feed roller 111.
Both ends of a guide shaft 103 and an auxiliary guide shaft 105, which are so positioned that they lie perpendicular to the direction in which the recording sheet 113 is conveyed, are fixed to the apparatus main body 100. And securely bonded to a slider 104 and an auxiliary slider 106 that, respectively, slidably engage the guide shaft 103 and the auxiliary guide shaft 105 is a carriage 102 on which recording means 101 is mounted. The recording means 101 is, for example, a type of ink-jet.
A carriage motor 107, which is fixed to the apparatus main body 100 and which has a pulley 108 securely fitted around its output shaft, is located at one end of the guide shaft 103, and an idle pulley 109 is rotatably secured at the other end. And fitted around the idle pulley 109 and the pulley 108 is a timing belt 110, one part of which is fixed to the carriage 102.
In addition, provided for the apparatus main body 100 is a controller 115, which is connected to the carriage motor 107 by a lead line 117 and to the paper feed motor 112 by another lead line (not shown). The controller 115 is also connected by a flexible print board 116 to the recording means 101 that is mounted on the carriage 102. With this arrangement, the controller 115 drives or controls the carriage motor 107, the paper feed motor 112 and the recording means 101.
It should be noted that a stepper motor having at least two phases may be employed as the carriage motor 107 because it provides superior control at a lower cost than does a common direct-current motor.
In Japanese Laid-Open Patent Application No. 53-82523, an apparatus for driving the carriage is disclosed wherein a motor is provided for the main body, and a wire that is fitted around a pulley, which is securely fitted around the output side of the motor, is guided by a rotary pulley that is attached to the main body.
In Japanese Laid-Open Patent Application No. 61-202875, a mechanism is disclosed wherein a motor is attached to a carriage, and is driven by a pinion gear that is fitted around the output shaft of the motor and that engages a rack that is provided for the main body.
In Japanese Laid-Open Patent Application No. 7-302307 or No. 10-269330, an information recording/reproducing apparatus is disclosed wherein an optical card, which is a card-shaped information recording medium, is mounted on a mounting table that serves as a carriage, and the mounting table is displaced relative to an optical head, which is a recording/reproducing head, so that information recording/reproducing is performed.
The conveying means used for this apparatus employs a transmission system, which includes an endless timing belt that transmits, to the mounting table, the driving force produced by a motor fixed to a main body, that moves the mounting table relative to the optical head. During this process, information recording/reproducing is performed by the optical head. FIG. 20 is a diagram showing the specific arrangement of this conveying means.
In FIG. 20, information recording tracks are formed on an optical card 200 at intervals of several xcexcm. The optical card 200 is a card-shaped information recording medium for which, to perform information recording/reproducing, a spot having a diameter of several xcexcm is formed by projecting a light beam between the tracks. The optical card 200 is mounted on a mounting table 201.
A guide shaft 202 is fixed at both ends to the main body, and a slider 203, which is securely bonded to the mounting table 201, slidably engages the guide shaft 202. An auxiliary guide shaft 204 is fixed at both ends to the main body, and is positioned so that it is parallel to the guide shaft 202. An auxiliary slider 205, which is securely bonded to the table 201, slidably engages the auxiliary guide shaft 204.
Further, a motor 206 is fixed to the main body; a pulley 207 is fitted around the output shaft of the motor 206; an idle pulley 208 is rotatably fixed to the main body; and a timing belt 209 that is fitted around the idle pulley 208 and the pulley 207 is partially secured to the table 201. A controller 216 is attached to the main body.
Optical detection devices 210 and 211 are attached to the main body to detect the position of a photointerrupter. Flexible print boards 212 and 213 electrically connect the optical detection devices 210 and 211 to the controller 216. A light shielding plate 214 is integrally formed with the mounting table 201 and detects its position in conjunction with the optical detection devices 210 and 211. And a lead line 215 is used to electrically connect the motor 206 and the controller 216.
The controller 216 drives or controls the motor 206 and the optical detection devices 210 and 211. The motor 206 rotates forward or backward to relatively displace the mounting table 201 and the optical card 200 in the directions indicated by an arrow G. It should be noted that as the motor 206 a two-phase stepper motor is employed because it provides superior control at a lower cost than does a common direct-current motor. To record/reproduce information, a light beam is emitted by an optical head 217.
An apparatus disclosed in Japanese Laid-Open Patent Application No. 10-269330 employs, as a card-shaped information recording medium, an optical card on which an IC chip is mounted. On the mounting table, a power terminal, to which the IC chip on the optical card is connected, is provided that is electrically connected to a controller in the main body by a flexible print board.
An information recording/reproducing apparatus that records/reproduces information relative to an optical disk comprises: a carriage, which moves in the direction of the diameter of the optical disk; and an optical head, which is mounted on the carriage. While the carriage is being moved, information is recorded on or reproduced from the optical disk. At this time, the position of the carriage is detected by position detection means (not shown), and control is provided for a drive actuator that drives the carriage.
This conveying means includes a lead thread that serves as one of the guide shafts for the carriage, and an internal threaded member that engages the lead thread and is provided in the carriage. To move the carriage, the lead thread is rotated by a motor in the main body.
This process will be specifically explained while referring to FIG. 21. In FIG. 21, an optical disk 300, a carriage 301 and a pickup 302, which serves as an optical head, are provided. The pickup 302 includes a projection light source, a light-receiving device, and a lens for focusing reflected light on the light-receiving device (none of these are shown).
A guide shaft 303, which is fixed at both ends to the main body, is slidably engaged by a slider 304, while a motor 305 is fixed to the main body and a pinion gear 306 is fitted around the output shaft of the motor 305. A threaded lead shaft 307 is rotatably attached to the main body, and a lead thread 307A on this shaft 307 engages an internal threaded member 301A in the carriage 301, while a gear 307B engages the pinion gear 306.
One end of a leaf spring 308 is securely bonded to the carriage 301 while the other end contacts and pushes against, using its own flexible force, the lead thread 307A of the threaded lead shaft 307 to remove the wobbling that occurs between the internal threaded member 301A of the carriage and the lead thread 307A. A controller 309, which is provided for the main body, is connected to the pickup 302 by a flexible print board 311 and drives or controls the motor 305 and the pickup 302.
As the motor 305 rotates forward or backward, the carriage 301 and the pickup 302 are moved along the face of the optical disk 300 in the directions indicated by an arrow G. It should be noted that a two-phase stepped motor is employed as the motor 305 because it provides superior control at a lower cost than does an ordinary direct-current motor.
However, in the serial recording apparatus in conventional example 1, the carriage motor 107 and the recording means 101 must be independently connected to the controller 115 electrically, and in this case the joint portion will become larger or the assembling costs will be increased. Further, since the timing belt 110 is formed as a ring and the space it encloses can not be used, it will interfere with efforts made to reduce the size of the apparatus.
In order to precisely drive the recording means 101 and the carriage 102, greater tension must be applied to the timing belt 110, and accordingly, the driving load will be increased. In addition, due to the increased load, side pressure will be applied to the output shaft of the motor, and the durability of the motor will be adversely affected.
Since, in the apparatus disclosed in Japanese Laid-Open Patent Application No. 53-82523, the motor is provided for the main body and the wire is fitted around the pulley that is securely bonded to the output shaft of the motor, an increase in the tension applied to the wire is required in order to cope with the drive load represented by the carriage. And when the strength of the tension applied to the wire is increased, a greater side pressure will be placed on the rotary pulley that is provided for the main body for guiding the wire, so that the friction at the rotating portion of the rotary pulley, i.e., at the portion attached to the main body, will be increased, as will the drive load. The durability of the rotary pulley will also be adversely affected, and additional parts will be needed and manufacturing costs will rise.
In the mechanism disclosed in Japanese Laid-Open Patent Application No. 61-202875, since the motor is provided on the carriage side, deterioration of the precision of the carriage positioning will occur due to the backlash produced between the rack and the pinion gear that is fitted around the output shaft of the motor. So long as deceleration of the motor is performed by a speed reduction mechanism, the backlash at the initial stage does not adversely affect the precision of the carriage positioning; however, the backlash at the last stage, i.e., near the rack, causes the precision with which the carriage is positioned to be greatly deteriorated. In order to eliminate the backlash, pressure must be applied to the pinion gear and the rack by some means in order to employ only one side for the engagement of the gear. As a result, the apparatus becomes complicated, and an increase in the load due to the pressure that is applied cannot be avoided. There is a method for driving the carriage using a lead thread instead of the rack and pinion gear, but to provide better precision for the positioning of the carriage, pressure must also be applied to the lead thread by some means in order to remove the gap at the lead screw, and an increase in the load cannot be avoided. Further, if a long rack and a long lead thread are employed, their manufacture is difficult, and the costs are increased.
In the conveying means of the information recording/reproducing apparatus in conventional example 2, the motor 206 and the optical detection means 210 and 211 must be independently, electrically connected to the controller 216, so that the connection joint becomes enlarged, and the assembly costs are increased. The timing belt 209 that is fitted around the pulleys 207 and 208 is shaped like a ring, and the space it encloses cannot be employed. Therefore, this will interfere with an effort made to reduce the size of the apparatus.
Since in order to accurately drive the mounting table 201, the timing belt should not be loose, considerable tension must be applied to the belt, and this increases the drive load. Especially because of side pressure due to the tension applied to the output shaft of the motor, durability of the motor is also adversely affected.
Furthermore, in the conveying means (the pickup feeding means) of the information recording/reproducing apparatus in conventional example 3, the motor and the pickup must be independently, electrically connected to the controller 309, so that the connection joint will be enlarged, and the assembly costs will be increased. And since the lead thread should be straight and uncurved, to prevent deformation, the diameter of a long lead thread must be increased, which in turn will lead to an increase in manufacturing costs and will interfere with an attempt to reduce the size of the apparatus. In addition, since to accurately drive the pickup and the carriage a greater pressure must be applied by the leaf spring, the driving load will be increased due friction induced resistance, and much damage due to friction will occur.
It is, therefore, one objective of the present invention to provide an apparatus, which includes a carriage scanning mechanism, that can be compactly made and for which assembly costs can be reduced, the drive load can be minimized and a carriage can be precisely driven, and to provide for the apparatus a recording apparatus, an information recording/reproducing apparatus, an information recording apparatus, an information reproduction apparatus, an information reading apparatus and an information erasing apparatus.
It is another objective of the present invention to provide an apparatus, which includes a carriage scanning mechanism, comprising:
a carriage capable of scanning in a predetermined scanning area;
drive means provided for the carriage; and
wire wound around an output unit of the drive means in the predetermined scanning area and extended under tension along a scanning direction of said carriage,
wherein the output unit around which the wire is wound moves along the wire upon scanning of the carriage is driven by the scanning drive means;
and to provide for the apparatus a recording apparatus, an information recording/reproducing apparatus, an information recording apparatus, an information reproduction apparatus, an information reading apparatus and an information erasing apparatus.
It is an additional objective of the present invention to provide an apparatus, which includes a carriage scanning mechanism, comprising:
a carriage capable of scanning in a predetermined scanning area;
drive means provided for the carriage, the drive means including at the least a motor and a rotary member to be driven by the motor; and
wire wound around an output unit of the drive means in the predetermined scanning area and extended under tension along a scanning direction of said carriage,
wherein the wire encircles the rotary member integer times;
and to provide for the apparatus a recording apparatus, an information recording/reproducing apparatus, an information recording apparatus, an information reproduction apparatus, an information reading apparatus and an information erasing apparatus.
It is further objective of the present invention to provide an apparatus, which includes a carriage scanning mechanism, comprising:
a carriage capable of scanning in a predetermined scanning area;
drive means provided for the carriage, the drive means including at the least a motor and a rotary member to be driven by the motor; and
wire wound around an output unit of the drive means in the predetermined scanning area and extended under tension along a scanning direction of said carriage,
wherein the wire is wound around the rotary member a predetermined number of times, and the ends of the wire are extended in opposite directions;
and to provide for the apparatus a recording apparatus, an information recording/reproducing apparatus, an information recording apparatus, an information reproduction apparatus, an information reading apparatus and an information erasing apparatus.
It is one more objective of the present invention to provide an apparatus, which includes a carriage scanning mechanism, comprising:
a carriage capable of scanning in a predetermined scanning area;
drive means provided for the carriage; and
wire wound around an output unit of the drive means in the predetermined scanning area and extended under tension along a scanning direction of said carriage,
wherein, during the scanning performed by the carriage, the wire substantially does not move in the direction in which the carriage is moving;
and to provide for the apparatus a recording apparatus, an information recording/reproducing apparatus, an information recording apparatus, an information reproduction apparatus, an information reading apparatus and an information erasing apparatus.